serverless-offline-lambda-to-lambda


A Serverless Offline plugin that exposes lambdas with no API Gateway event via HTTP, to allow offline direct lambda-to-lambda interactions.

Note - this requires the plugin serverless-offline.

Installation

Go to your project directory and install the plugin by running :

for npm users

``bash
npm install -D serverless-offline-lambda-to-lambda
`

for yarn users

`bash
yarn add serverless-offline-lambda-to-lambda -D
`

Setup

Open your serverless.yml configuration file and

- add a plugins section
- add serverless-offline-lambda-to-lambda plugin

`
plugins:
- serverless-offline-lambda-to-lambda
`

You may also want to change the port that the plugin runs on - you can do this by specifying the following custom config in your serverless.yml file:

`yml
custom:
serverless-offline:
port: 4000
`

Running & Calling

To run:

`
servlerless offline start
`

The plugin will create api-gateway proxies for all lambdas.

You will see output like this:

`bash
sls offline start

Serverless: Running Serverless Offline with lambda-to-lambda support
Serverless: Starting Offline: dev/us-east-1.

Serverless: Routes for lambda-func:
Serverless: (none)

Serverless: Routes for my-sls-project-dev-lambda-func_proxy:
Serverless: POST /proxy/my-sls-project-dev-lambda-func
Serverless: POST /2015-03-31/functions/my-sls-project-dev-lambda-func/invocations
`

$3

The body of the POST should match the JSON data that would ordinarily be passed in a lambda-to-lambda call. i.e.

`bash
curl -X POST \
http://localhost:4000/proxy/my-sls-project-dev-lambda-func \
-H 'Cache-Control: no-cache' \
-H 'Content-Type: application/json' \
-d '{
"some-key": "some-value",
"other-key": false
}'
`

$3

You may also invoke the function by using the AWS SDK on your client side...
This can be done by specifying a custom "endpoint" in your Lambda configuration like so:

`javascript
var AWS = require("aws-sdk");
AWS.config.region = "us-east-1";

let lambda = new AWS.Lambda({
region: "us-east-1",
endpoint: "http://localhost:4000"
});

var lambda_args = {
"some-key": "some-value",
"other-key": false
};

var params = {
FunctionName: "my-sls-project-dev-lambda-func", // the lambda function we are going to invoke
Payload: JSON.stringify(lambda_args)
};

lambda.invoke(params, function(err, data) {
if (err) {
console.error(err);
} else {
console.dir(data);
}
});
``